There are over 100 species of Bentgrass (Agrostis) but only two are used to any great extent as golf course turf. Bentgrass is well adapted to close mowing due to its prostrate growth habit. They grow best in moist uncompacted soils and have broad temperature hardiness.
Creeping bentgrass (Agrostis palustris) is so named due to its ability to creep laterally by stolons. The stolons are able to root at the nodes producing a new plant. Creeping bentgrass is the plant of choice for fairways, tees and greens where the height of cut is below one-half inch.
Creeping bentgrass (Agrostis palustris) is a perennial cool season grass that forms a dense mat. The grass spreads by profuse creeping stolons and basal tillers and possesses rather vigorous, shallow roots. Stems, or stolons, are decumbent (creeping) and slender and produce long narrow leaves. Leaf blades are smooth on the upper surface and ridged on the underside, are approximately 1 to 3 mm wide and bluish green in appearance. The ligule is long, membranous, finely toothed or entire and rounded, auricles are absent.
Developing new grass species is difficult, time consuming, and expensive. The developer must sift through thousands of prospective grasses listed in botanical literature, identify promising grasses, and often travel thousands of miles to locate, isolate, identify, transport, quarantine, grow, test, and breed these grasses. This process can take more than 10 years to develop acceptable cultivars. Furthermore, as it turns out, most prospective grasses in nature have no commercial turf value, due to their inability to generate an acceptable ground cover when mowed. The vast majority of natural grasses cannot produce a plush lawn under continuing defoliation.
Yet another complexity facing the plant developer is the unresponsiveness of many wild grasses to plant breeding. The vast majority of wildland grasses lack genetic potential for refinement into desirable turfgrass cultivars. Only after considerable investment in collection and breeding does the developer discover which grass species can be successful bred and which cannot.
The Agrostis genus--better known as the bentgrasses--is comprised of over 100 species, several of which have been developed into successful turfgrasses. One Agrostis in particular, A. stolonifera or creeping bentgrass, has become the preeminent grass for golf course putting greens the world over. Another Agrostis species, colonial bentgrass (A. tenuis Sibth.), has been bred into a golf course grass useful on tees and fairways in cooler regions. Two or three other Agrostis species find minor turf application, mostly for golf, tennis courts, bowling greens, or an occasional home lawn.
The Agrostis genus is widely distributed throughout the world with representative species found on all of the northern continents. However, of the present-day bentgrass species in use as turfgrasses, all originated from Europe. The original seed of these plants was brought to the US during colonial times.
America has an abundance of native bentgrass species (A. S. Hitchcock, 1951, Manual of the grasses of the United States. USDA Misc. Publ. 200) but none are commercially useable as turf grass.
Agrostis palustris (stolonifera) is found in nature throughout the mountains of New Mexico, Arizona, and California, along the Rockies, and north to Fairbanks, Ak. Commercial bentgrass species (creeping bentgrass, colonial bentgrass, etc.) all possess stolons (above-ground running stems) and/or rhizomes (below ground running stems). Hitchcock describes Agrostis palustris (stolonifera) as follows:
Culms slender, tufted, 10 to 30 cm tall, leaves mostly basal, the blades narrow; panicle loosely spreading, 5 to 10 cm long, the branches capillary, flexuous, minutely scabrous; spikelets 1.5 to 2.5 mm long; lemma about 1.3 mm long, awnless; palea minute. Differs from A. scabra in the smaller spikelets and in the narrower panicle with shorter flexuous branches. PA1 Delicate, loosely-tufted, glabrous, perennial, 10-30 cm high; blades flat, narrow, 1-6 cm long; panicle loose, green or purple, 5-10 cm long; rays capillary; spikelets about 1.5 mm long; lower glume scabrous on the keel, slightly larger than the upper; lemma truncate, awnless, 1 mm long; palea minute.
Piper and Beattie (Charles V. Piper and R. Kent Beattie, 1914, Flora of Southeastern Washington and adjacent Idaho, New Era Printing Co., Lancaster, Pa.) studied the natural occurrence of Agrostis palustris (stolonifera). They found it common to the alpine woods of the Craig Mountains. Their botanical description is as follows:
Correll and Correll (D. S. Correll and H. B. Correll, 1972, Aquatic and wetland plants of the Southwestern United States, Stanford Univ. Press, Stanford, Calif.) reported that Agrostis palustris (stolonifera) is an important native wetland species in moist mountain meadows, swamps, shallow water of ponds, lakes, along streams, and on sand-gravel bars in river beds throughout the West. DeBenedetti and Parsons (S. H. DeBenedetti and D. J. Parsons, 1984, Postfire succession in a Sierran subalpine meadow, Amer. Midland Naturalist 111:118-125) concluded that Agrostis palustris (stolonifera) was the most important native grass species present in post-fire succession of subalpine grasslands in California. Its tenacious growth under adverse conditions makes it a valuable forage for wildlife.